Messages - ssilver0210

It is very difficult to explain these concepts in the abstract, so if you have an assumption question that is causing you difficulty, you should consider posting the Prep Test section and number.

In general, though, the reason why the negation technique works is because within the answer choices, you are looking for a statement that must be true for the conclusion of the argument to be valid (necessary assumption questions). If you negate an answer choice, and after negating that choice the conclusion to the passage is still valid, then the answer choice (before it was negated) need not have been true for the conclusion to be valid.

If you negate an answer choice, and in doing so the conclusion to the passage is no longer valid, then you've found a statement that must be true for the conclusion to be valid.

Once you've found a statement that must be true for the conclusion of the passage to be valid, you've found the statement on which the argument depends, which is often the way the question is worded.

The reason why "E" is the correct answer is because it brings the time factor into the equation. In other words, in choice B, it's possible that people who fly today will not be less likely to contact illnesses, if, for example, their flight lasts less than one hour. In that case, their cabin air will have been replenished just as many times as it would have been in 1980 (once).

On the other hand, choice E tells us that it is a 2 hour flight. In 1980, a two-hour flight will have had the cabin air replenished four times, but today, that same flight will only have the cabin air replenished 2 times. We know that the less frequently the air is replenished, the more CO2 in the environment. So, because this specific 2-hour flight would replenish the cabin air less frequently, there would be a lower level of C02 on the 1980 flight than on the same flight today. (choice E)

21: We know that prime purchasers will not buy the software if the cost to train employees on how to use the software is high. We also know that the costs will be high to train employees to use software which requires memorization of unfamiliar commands.

We know, based on the two statements above, that the prime purchasers will not be purchasing the software which requires memorization of unfamiliar commands. But in order for it to be true that the software will not be successful if it requires users to memorize unfamiliar commands (the conclusion of the passage), it also must be true that success can not be achieved for software, unless prime purchasers purchase the software. (Choice C)

If success can be achieved even if prime purchasers do not purchase the software, then the fact that the software requires memorization of unfamiliar commands (which will deter prime purchasers from purchasing the software) will not prevent the software from being successful.

24: The passage here states that because, over the last 25 years, the average price paid for a new car has increased in relation to average individual income, we can conclude that individuals who buy new cars today, spend, on average, more than individuals spent on cars 25 years ago. Keep in mind, that we're not told that the average price paid by individuals has increased.

Because we're not told that the average price paid by individuals has increased, the conclusion that individuals pay a larger amount today than they did 25 years ago is open to question. And if sales to individuals make up a smaller amount today than they did 25 years ago (choice E) then the fact that cars are being bought today at a higher price (perhaps by companies rather than individuals) weakens the conclusion that individuals who buy cars today spend more in relation to their income than they did 25 years ago.

Assume that all other employees within the company made more than 42,000. That would mean that the average annual salary of those employees could not be less than 42,000. If the average annual salary of all other employees was 42,000 or more, than the average annual salary of all employees could not be 40,000, because the average of all other employees would not be low enough to bring the average of the other two groups down from 46,000 to 40,000.

So, at least one employee had to make less than 42,000 for there to be any possibility that the average of all employees is 40,000. (Choice C.)

#24: The flaw in the reasoning is first the passage claims that because titanium was found in the B-36, it was probably printed by Gutenberg. To make that assumption, it would have to be true that no people (or not many people) other than Gutenberg printed documents using Titanium Ink.

But the passage then goes to say it is no longer justifiable to claim that the Vinland map is not an authentic pre-15th century map, simply because titanium was found in its ink. That statement implies that documents other than those printed by Gutenberg prior to 1500 (specifically, the Vinland Map) had used titanium ink.

If documents other than those printed by Gutenberg had used titanium ink, then the assumption that the B-36 was printed by Gutenberg simply because it was found to have titanium ink, falls flat.

Choice A says that the results of the analysis are interpreted as indicating that the use of titanium as an ingredient in fifteenth-century ink both was restricted (to Gutenberg), and not restricted (to Gutenberg). In other words, the two conclusions contradict each other.

An intro to Logic book would have helpful information, but it would also contain information which is beyond the scope of the LSAT. If you knew what to zone in on within the logic book, then I suppose it couldn't really hurt to look through it, but if you ended up spending time studying material irrelevant to the LSAT, then not only might it not help your score, but it could hurt it, because the time you're spending trying to understand concepts that you will not need to know for the LSAT, could have been spent trying to understand concepts that you will need to know.

Just to add to the explanation above, let's take a few numbers as examples:

Assume 400 students attend the college

Let's say 100 students pay x to go to the college.

300 students pay 2x to go to the college.

The total amount of money the college brings in from tuition is $500,000

Ten years pass......

Now, 240 students are paying x to go to the college

160 students are paying 2x

The college is still making $500,000

The amount of people paying 2x has dropped, so that the only way for the college to still make the amount it made ten years earlier when there were more people paying 2x is if the value of x and 2x have gone up. If the value of x and 2x have increased, then the fact that there has been a decrease in the number of people paying 2x, would not necessarily require that the college make less money.

I'm not exactly sure why they tell you not to study, but if I had to guess, your first choice is probably more accurate. I'm guessing that they figure a majority of students start off pretty low, and that it's best these students allow their instructors to take them through the process, before even trying it out on their own.

Not so sure this applies to you, as your scores are high. I don't think it would hurt at all to study before taking the course. If anything, you might find that the course has less value to you than to other students who are having more difficulty with material. But the fact that that might be true, only means you'll have to put in the time on your own as well to get your score to the highest possible point.

Normally I would agree that since you've just started studying, you should be practicing LR untimed, because it's really a step-by-step process, and learning to think and reason the way the LSAT requires should take precedence over worrying about timing issues. Timing is of course extremely important, but it's not generally something that needs to be worried about when someone is first beginning to study.

You've started at a high score, though, so you seem to be at the point already, where you've developed the reasoning ability needed to do well, and you just need to fine-tune a few things. In a situation like yours, you might be best sticking to the time and then going back after the test, and focusing clearly on your mistakes, especially where you've gone wrong on your reasoning.

If you were to take the test untimed, it's possible you'll get a few right that you wouldn't have gotten right under timed conditions. And under untimed conditions, you might not realize which questions would have caused you difficulty had the test been timed.